Grabbing Power

When planning new electrical service, begin by deciding where you can tap into power. If you are adding a couple of receptacles or lights, it is usually easiest to grab power from a nearby receptacle or junction box. First, however, make sure the new service doesn't overload the circuit.

If nearby boxes are on circuits that do not have enough available wattage for the new service, try a box farther away. If no circuit is usable or if the new service needs its own circuit, run cable all the way to the service panel and connect to a new circuit breaker.

If you need to, run cable through walls and ceilings to get at power.

Checklist

Time
About 2 hours to connect new cable to an existing receptacle or junction box (not including cutting a pathway for the cable and patching walls)

To grab power from a receptacle, make a load list to verify that there is room on the circuit for new service. Shut off power to the circuit and test that power is not present. Disconnect the receptacle.

If the box is inside a wall, cut a hole into the wall to get at the box or pull the box out. Pry with a flat pry bar, then remove the nails or cut through them with a close-work hacksaw or reciprocating saw.

If two cables enter the box, the receptacle is in the middle of a run. Splice the wires and connect to terminals with pigtails as shown. The purpose of pigtails is to avoid multiple connections to one terminal screw where they could easily short or come loose. Make pigtails by removing the sheathing from about 8 inches of NM cable. Strip about 3/4 inch for each end of the black and white wires and attach them as shown.